Multilayer technique: the addition of the plastic film was the initial step to produce brick containers impermeable to liquids and warmth-sealable. During the 1960s, an aluminum foil began to be included to the cardboard container to be certain much better safety and lengthen the shelf life of the packaged product. https://sustainablemilkcarton.blogspot.com/2024/12/gabletop-pak-leading-way-in-sustainable.html